import { computed, nextTick, onMounted, ref } from 'vue'

import { useSystemState } from '../../composables/useSystemState.js'
import { recognizeOcrFiles } from '../../services/ocr.js'
import { runOrchestrator } from '../../services/orchestrator.js'

const DEFAULT_REQUEST = {
  id: 'BR240712001',
  reason: '客户方案汇报',
  city: '上海',
  period: '07-08 ~ 07-11',
  applyTime: '2024-07-07',
  amount: '¥3,680.00',
  node: '财务复核',
  approval: '主管审批中',
  travel: '已订酒店 / 机票'
}

const SOURCE_LABELS = {
  workbench: '来自个人工作台',
  topbar: '来自发起报销',
  detail: '来自智能录入',
  upload: '来自附件上传',
  requests: '来自报销列表'
}

const SCENARIO_LABELS = {
  expense: '报销',
  accounts_receivable: '应收',
  accounts_payable: '应付',
  knowledge: '知识',
  unknown: '通用'
}

const INTENT_LABELS = {
  query: '查询',
  explain: '解释',
  compare: '对比',
  risk_check: '风险检查',
  draft: '草稿生成',
  operate: '动作请求'
}

let messageSeed = 0

function nowTime() {
  return new Date().toLocaleTimeString('zh-CN', {
    hour: '2-digit',
    minute: '2-digit',
    hour12: false
  })
}

function createMessage(role, text, attachments = [], extras = {}) {
  messageSeed += 1
  return {
    id: `msg-${messageSeed}`,
    role,
    text,
    attachments,
    time: nowTime(),
    meta: [],
    citations: [],
    suggestedActions: [],
    draftPayload: null,
    riskFlags: [],
    ...extras
  }
}

function sanitizeRequest(request) {
  if (!request) return { ...DEFAULT_REQUEST }
  return {
    id: request.id ?? DEFAULT_REQUEST.id,
    reason: request.reason ?? DEFAULT_REQUEST.reason,
    city: request.city ?? DEFAULT_REQUEST.city,
    period: request.period ?? DEFAULT_REQUEST.period,
    applyTime: request.applyTime ?? DEFAULT_REQUEST.applyTime,
    amount: request.amount ?? DEFAULT_REQUEST.amount,
    node: request.node ?? DEFAULT_REQUEST.node,
    approval: request.approval ?? DEFAULT_REQUEST.approval,
    travel: request.travel ?? DEFAULT_REQUEST.travel
  }
}

function resolveStatusLabel(status) {
  if (status === 'succeeded') return '已完成'
  if (status === 'blocked') return '已阻断'
  return '失败'
}

function resolveStatusTone(status) {
  if (status === 'succeeded') return 'success'
  if (status === 'blocked') return 'warning'
  return 'note'
}

function buildMessageMeta(payload, fileNames = []) {
  const items = []

  if (payload?.selected_agent) {
    items.push(`Agent: ${payload.selected_agent}`)
  }

  if (payload?.permission_level) {
    items.push(`权限: ${payload.permission_level}`)
  }

  if (payload?.trace_summary?.tool_count) {
    items.push(`工具: ${payload.trace_summary.tool_count}`)
  }

  if (payload?.trace_summary?.degraded) {
    items.push('已降级')
  }

  if (payload?.requires_confirmation) {
    items.push('待确认')
  }

  if (payload?.run_id) {
    items.push(`Run: ${payload.run_id}`)
  }

  if (fileNames.length) {
    items.push(`附件: ${fileNames.length}`)
  }

  return items
}

function normalizeOcrDocuments(payload) {
  const documents = Array.isArray(payload?.documents) ? payload.documents : []
  return documents.slice(0, 5).map((item) => ({
    filename: item.filename,
    summary: item.summary,
    text: String(item.text || '').slice(0, 240),
    avg_score: Number(item.avg_score || 0),
    line_count: Number(item.line_count || 0),
    warnings: Array.isArray(item.warnings) ? item.warnings : []
  }))
}

function buildOcrSummary(payload) {
  const parts = normalizeOcrDocuments(payload)
    .map((item) => `${item.filename}：${item.summary || item.text}`)
    .filter(Boolean)

  return parts.join('；')
}

function buildWelcomeInsight(entrySource, linkedRequest) {
  return {
    intent: 'welcome',
    metricLabel: '运行模式',
    metricValue: 'Ready',
    title: entrySource === 'detail' ? `已关联 ${linkedRequest.id}` : '已接入真实智能体对话',
    summary:
      entrySource === 'detail'
        ? '发送消息后会直接调用 Orchestrator，并返回真实的规则引用、建议动作和草稿结果。'
        : '这里不再使用前端本地意图模拟，所有发送内容都会进入真实 Orchestrator 调度链路。',
    agent: null
  }
}

function buildErrorInsight(error, fileNames = []) {
  return {
    intent: 'agent',
    metricLabel: '运行状态',
    metricValue: '失败',
    title: '智能体调用失败',
    summary: error?.message || '无法连接后端 Orchestrator。',
    agent: {
      runId: '未生成',
      selectedAgent: 'orchestrator',
      scenario: '未知',
      intent: '未知',
      permissionLevel: 'unknown',
      routeReason: 'request_failed',
      requiresConfirmation: false,
      degraded: false,
      fileNames,
      citations: [],
      suggestedActions: [],
      draftPayload: null,
      riskFlags: [],
      toolCount: 0,
      failedToolCount: 0,
      selectedCapabilityCodes: [],
      statusLabel: '失败',
      statusTone: 'note'
    }
  }
}

function buildAgentInsight(payload, fileNames = []) {
  const trace = payload?.trace_summary || {}
  const result = payload?.result || {}
  const statusLabel = resolveStatusLabel(payload?.status)

  return {
    intent: 'agent',
    metricLabel: '运行状态',
    metricValue: statusLabel,
    title:
      result?.draft_payload?.title ||
      `${SCENARIO_LABELS[trace?.scenario] || '通用'}${INTENT_LABELS[trace?.intent] || '处理'}结果`,
    summary: result?.answer || result?.message || '智能体已完成处理。',
    agent: {
      runId: payload?.run_id || '未生成',
      selectedAgent: payload?.selected_agent || 'orchestrator',
      scenario: SCENARIO_LABELS[trace?.scenario] || trace?.scenario || '未知',
      intent: INTENT_LABELS[trace?.intent] || trace?.intent || '未知',
      permissionLevel: payload?.permission_level || 'unknown',
      routeReason: payload?.route_reason || 'unknown',
      requiresConfirmation: Boolean(payload?.requires_confirmation),
      degraded: Boolean(trace?.degraded),
      fileNames,
      citations: Array.isArray(result?.citations) ? result.citations : [],
      suggestedActions: Array.isArray(result?.suggested_actions) ? result.suggested_actions : [],
      draftPayload: result?.draft_payload || null,
      riskFlags: Array.isArray(result?.risk_flags) ? result.risk_flags : [],
      toolCount: Number(trace?.tool_count || 0),
      failedToolCount: Number(trace?.failed_tool_count || 0),
      selectedCapabilityCodes: Array.isArray(trace?.selected_capability_codes)
        ? trace.selected_capability_codes
        : [],
      statusLabel,
      statusTone: resolveStatusTone(payload?.status)
    }
  }
}

export default {
  name: 'TravelReimbursementCreateView',
  props: {
    initialPrompt: {
      type: String,
      default: ''
    },
    initialFiles: {
      type: Array,
      default: () => []
    },
    entrySource: {
      type: String,
      default: 'requests'
    },
    requestContext: {
      type: Object,
      default: null
    }
  },
  emits: ['close'],
  setup(props, { emit }) {
    const { currentUser } = useSystemState()

    const fileInputRef = ref(null)
    const messageListRef = ref(null)
    const composerDraft = ref('')
    const attachedFiles = ref([])
    const submitting = ref(false)
    const messages = ref([])
    const linkedRequest = computed(() => sanitizeRequest(props.requestContext))

    const currentInsight = ref(buildWelcomeInsight(props.entrySource, linkedRequest.value))
    const sourceLabel = computed(() => SOURCE_LABELS[props.entrySource] ?? '来自 AI 工作台')
    const canSubmit = computed(
      () => !submitting.value && Boolean(composerDraft.value.trim() || attachedFiles.value.length)
    )
    const showInsightPanel = computed(() => currentInsight.value.intent !== 'welcome')
    const composerPlaceholder = computed(() => {
      if (props.entrySource === 'detail') {
        return `例如：解释一下 ${linkedRequest.value.id} 的报销风险，或帮我生成处理意见草稿。`
      }
      return '例如：查一下本周报销金额、解释酒店超标风险，或根据附件生成报销草稿。'
    })
    const currentIntentLabel = computed(() => {
      const labels = {
        welcome: '等待输入',
        agent: '真实智能体'
      }
      return labels[currentInsight.value.intent] ?? 'AI 处理中'
    })

    const shortcuts = computed(() => {
      if (props.entrySource === 'detail') {
        return [
          {
            label: '解释风险原因',
            icon: 'mdi mdi-shield-alert-outline',
            prompt: `解释一下 ${linkedRequest.value.id} 为什么会被拦截`
          },
          {
            label: '生成处理意见',
            icon: 'mdi mdi-file-document-edit-outline',
            prompt: `帮我给 ${linkedRequest.value.id} 生成处理意见草稿`
          },
          {
            label: '列出补件清单',
            icon: 'mdi mdi-format-list-checks',
            prompt: `帮我列出 ${linkedRequest.value.id} 还需要补哪些附件`
          },
          {
            label: '引用相关制度',
            icon: 'mdi mdi-book-open-variant-outline',
            prompt: `解释一下 ${linkedRequest.value.id} 相关的报销制度依据`
          }
        ]
      }

      return [
        {
          label: '查本周报销金额',
          icon: 'mdi mdi-cash-multiple',
          prompt: '查一下本周报销金额'
        },
        {
          label: '解释报销风险',
          icon: 'mdi mdi-shield-alert-outline',
          prompt: '为什么酒店超标报销不能直接通过'
        },
        {
          label: '生成报销草稿',
          icon: 'mdi mdi-file-document-edit-outline',
          prompt: '帮我生成一份差旅报销草稿'
        },
        {
          label: '查待付款金额',
          icon: 'mdi mdi-bank-transfer-out',
          prompt: '供应商B待付款多少'
        }
      ]
    })

    messages.value = [
      createMessage(
        'assistant',
        props.entrySource === 'detail'
          ? `已进入统一对话工作台，当前关联单据 ${linkedRequest.value.id}。你的提问会直接进入真实智能体链路。`
          : '这里是统一对话入口。你发送的内容会直接进入真实 Orchestrator 和 User Agent。'
      )
    ]

    onMounted(() => {
      currentInsight.value = buildWelcomeInsight(props.entrySource, linkedRequest.value)
      if (props.initialPrompt?.trim() || props.initialFiles.length) {
        composerDraft.value = props.initialPrompt.trim()
        attachedFiles.value = Array.from(props.initialFiles)
        submitComposer()
      } else {
        nextTick(scrollToBottom)
      }
    })

    function scrollToBottom() {
      if (!messageListRef.value) return
      messageListRef.value.scrollTop = messageListRef.value.scrollHeight
    }

    function replaceMessage(messageId, nextMessage) {
      const index = messages.value.findIndex((item) => item.id === messageId)
      if (index === -1) {
        messages.value.push(nextMessage)
        return
      }
      messages.value.splice(index, 1, nextMessage)
    }

    function triggerFileUpload() {
      if (submitting.value) return
      fileInputRef.value?.click()
    }

    function handleFilesChange(event) {
      attachedFiles.value = Array.from(event.target.files ?? [])
    }

    function runShortcut(prompt) {
      composerDraft.value = prompt
      submitComposer()
    }

    function buildBackendMessage(rawText, fileNames, ocrSummary = '') {
      const parts = []
      const normalizedText = String(rawText || '').trim()

      if (normalizedText) {
        parts.push(normalizedText)
      } else if (fileNames.length) {
        parts.push(`我上传了 ${fileNames.length} 份票据，请结合附件名称给出报销建议并尽量生成草稿。`)
      }

      if (fileNames.length) {
        parts.push(`附件名称：${fileNames.join('、')}`)
      }

      if (ocrSummary) {
        parts.push(`OCR摘要：${ocrSummary}`)
      }

      if (props.entrySource === 'detail') {
        parts.push(`关联单号：${linkedRequest.value.id}`)
      }

      return parts.join('\n')
    }

    async function submitComposer() {
      if (!canSubmit.value) return

      const rawText = composerDraft.value.trim()
      const files = Array.from(attachedFiles.value)
      const fileNames = files.map((file) => file.name)
      const userText =
        rawText || `我上传了 ${fileNames.length} 份票据，请帮我识别并给出报销建议。`

      messages.value.push(createMessage('user', userText, fileNames))

      const pendingMessage = createMessage('assistant', 'Orchestrator 正在处理中...', [], {
        meta: ['运行中']
      })
      messages.value.push(pendingMessage)

      composerDraft.value = ''
      attachedFiles.value = []
      if (fileInputRef.value) {
        fileInputRef.value.value = ''
      }

      submitting.value = true
      nextTick(scrollToBottom)

      try {
        const user = currentUser.value || {}
        let ocrPayload = null
        let ocrSummary = ''
        let ocrDocuments = []

        if (files.length) {
          try {
            ocrPayload = await recognizeOcrFiles(files)
            ocrSummary = buildOcrSummary(ocrPayload)
            ocrDocuments = normalizeOcrDocuments(ocrPayload)
          } catch (error) {
            console.warn('OCR request failed:', error)
          }
        }

        const backendMessage = buildBackendMessage(rawText, fileNames, ocrSummary)
        const payload = await runOrchestrator({
          source: 'user_message',
          user_id: user.username || user.name || 'anonymous',
          message: backendMessage,
          context_json: {
            role_codes: Array.isArray(user.roleCodes) ? user.roleCodes : [],
            is_admin: Boolean(user.isAdmin),
            name: user.name || '',
            role: user.role || '',
            entry_source: props.entrySource,
            request_context: linkedRequest.value,
            attachment_names: fileNames,
            attachment_count: fileNames.length,
            ocr_summary: ocrSummary,
            ocr_documents: ocrDocuments
          }
        })

        replaceMessage(
          pendingMessage.id,
          createMessage('assistant', payload?.result?.answer || payload?.result?.message || '智能体已完成处理。', [], {
            meta: buildMessageMeta(payload, fileNames),
            citations: Array.isArray(payload?.result?.citations) ? payload.result.citations : [],
            suggestedActions: Array.isArray(payload?.result?.suggested_actions)
              ? payload.result.suggested_actions
              : [],
            draftPayload: payload?.result?.draft_payload || null,
            riskFlags: Array.isArray(payload?.result?.risk_flags) ? payload.result.risk_flags : []
          })
        )
        currentInsight.value = buildAgentInsight(payload, fileNames)
      } catch (error) {
        replaceMessage(
          pendingMessage.id,
          createMessage(
            'assistant',
            error?.message || '无法连接后端 Orchestrator，请稍后重试。',
            [],
            {
              meta: ['调用失败']
            }
          )
        )
        currentInsight.value = buildErrorInsight(error, fileNames)
      } finally {
        submitting.value = false
        nextTick(scrollToBottom)
      }
    }

    return {
      emit,
      fileInputRef,
      messageListRef,
      composerDraft,
      attachedFiles,
      submitting,
      messages,
      currentInsight,
      linkedRequest,
      sourceLabel,
      canSubmit,
      showInsightPanel,
      composerPlaceholder,
      currentIntentLabel,
      shortcuts,
      triggerFileUpload,
      handleFilesChange,
      runShortcut,
      submitComposer
    }
  }
}